Paper manufacture



Aug. 7, 1934.,

1.. M. YOERG PAPER MANUFACTURE Filed Nov. 16. 1932 l INVENTOR.

ATTORNEY.

v. 9 S 9 9 0 R 9 Patented Aug. 7, 1934 UNITED STATES PAPER MANUFACTURE Leon M. Yoerg, Holyoke', Masa, assignor to American Writing Paper Company, Holyoke, Masa, a corporation of Delaware Application November 16, 1932, Serial No. 642,908

1 Claim.

This invention relates to improvements in paper manufacture and is directed more particularly to improvements in the method of and apparatus for producing paper having hardened and 5 waterproofed surfaces. This application is a continuation in part of an application Serial No. 549,151, filed July '7, 1931.

The principal objects of this invention are directed to improvements in the process of and apparatus for making paper having waterproofed and hardened surfaces as distinguished from paper which is hardened throughout the main body thereof. According to special features of the invention the novel process contemplates the forming, drying, sizing and hardening steps by a continuous operation so that the paper which is uniform in its important characteristics may be produced in an economical manner.

According to certain features of the invention the surfaces of the paper are sized in a novel way and a hardening medium is applied thereto in such a way that .the hardening material is applied to the surface only thereof. In that way extremely flexible and pliable paper is produced which has the desired hardened and waterproofed surface.

Various novel features and advantages of the invention will be more fully hereinafter referred to in connection with the accompanying description taken in connection with the drawing wherein;

Fig. 1 is a diagrammatic elevational view of an apparatussuitable for carrying out the novel process of the invention, and

Fig. 2 is an elevational view of certain parts of the apparatus shown in Fig. 1.

Referring now to the drawing in detail the invention will be fully described.

In Fig. 1 there is shown in a diagrammatic way an apparatus suitable for carrying out the novel process of the invention but it will be understood that an apparatus may be arranged in various ways in order to carry out .the novel process and produce the desired results. In the apparatus shown a web forming element which may be a Fourdrinier wire is indicated at 2 and is suitably supported in the usual way on drmns or cylinders 4.

A delivery means 6 is shown for supplyin paper making material to the wire. This, as usual, may be of fibrous material suspended in water and will be delivered to the Fourdrinier wire in the desired amounts. One or more press devices such as 8 and 10 receive the web W formed on the wire.

These may include press rolls 12 and 14 and endless aprons 16 and 18 associated with the lower rolls suitably supported on idlers 20 and 22.

A web of paper W formed on the Fourdrinier wire passes through the press rolls and through a dryer D. This dryer may include a plurality of drying cylinders indicated by 24 and 26 and endless belts or felts indicated by'25 and 2'7 supported on rollers 28 and 30 are associated with the drying cylinders in the usual way.

Adjacent the dryer mechanism D there is a size device indicated generally by S. This may consist of a vat or tank 36 having rolls 38 associated therewith while other rolls 40 are provided for guiding the web W from the dryer D into and through the vat where it passes between the rolls 38.

A dryer indicated generally by 50 may consist of a plurality of drying cylinders 52 over which the web W passes and a calender stack is represented at 58 which may consist of a plurality of rolls 60 so that the web from the dryer may be passed through the rolls and finally wound up in roll form indicated by 64.

Means for applying hardening medium to the web and indicated generally by H is disposed so preferably between the size applying device S and the dryer 50. This includes a conduit '70 having a plurality of discharge outlets '72 spaced therealong which may be in the form of nozzles. This conduit '70 may be supplied with a hardened medium in any well known manner but in the form of the invention shown a supply tank or vat '73 is connected by a pipe '74 to the conduit so that hardening material may flow into the conduit. A valve '76 in the pipe line '74 is provided to control the flow of material into the said conduit.

An air header in the form of a pipe '78 is disposed more orless parallel to the conduit 70 and is provided with a plurality of outlets spaced therealong which may be in the form of nozzles indicated by 80. Air from the nozzles is directed towards the nozzles '72 so as to blow hardening medium therefrom.

A heater 82 is supported beneath the paper web 10 and this may be in the'form of a pipe, cylinder or the like. In the form of the invention shown the pipe may be heated as by steam delivered thereto by means of a pipe 84.- It is desired that the hardening medium be blown onto the heater so that 1 5 it is vaporized or volatilized. In lieu of the heater described it may be desired to employ what is known asra hot plate; that is, a plate member which is heated by resistance coils, or other means.

In carrying out the invention, I make use of the 1.10

2 aeoaaea fact that such a hardening medium as formaldehyde has more or less of an aflinity for sizemade from animal glue but not for resin size, wherefore it reacts more particularly with the animal size to produce the hardening eilect.

In accordance with the invention the paper making material or stuff contains resin size so that of course the body of the web contains resin size. As the paper web passes through the press rolls and dryer and then through the tank 36 of the size device which contains sizing made from animal glue the said size is applied to the surfaces only. This is because the rolls 38 squeeze of! excess size so that the size does not penetrate the web.

As the web leaves the size device with the size applied to the surfaces it travels past the hardening device. The hardening medium which may be. formaldehyde is blown onto the heater by which it is vaporized so that extremely small particles of the medium strike the paper for uniform distribution. Since the animal size is carried by the surfaces only of the paper the hardening medium reacts therewith to produce hardening of the surfaces only.

It may be mentioned that the vaporized formaldehyde strikes the lower side of the web but since the main body thereof is not saturated with animal size the hardener does not react with resin size in the main body of the paper. Instead, the hardener passes through the web and reacts with the. animal size on the upper side to bring about the hardening on both sides as distinguished from the hardening eil'ect throughout the main body of the paper.

In carrying out the novel process with the apparatus described, the paper making material which is delivered to the paper making element 2 and which contains resin size is formed into a web. The web is pressed and dried and passes through the size applying device described so that animal size is applied to the surfaces thereof. Then, vaporized hardening medium is applied to the web after which the web is quickly dried, calendered, if desired, and finally reeled up. v

Since the hardening effect is brought about by the reaction of the formaldehyde and animal size the effect may be varied by varying the collagen content of the sizing medium which may be made from such glue-producing materials as bone, hides or the like.

As has been explained, it is desired that the hardening medium such as formaldehyde be applied to the surfaces of the web only rather than the main body thereof so that the web will have a hardened water proofed surface and be pliable and bendable.

Having described the invention in theform at present preferred what I now desire to claim and secure by Letters Patent of the United States is: The continuous process of making paper having hardened surfaces which consists in, forming a paper web containing resin size in its bodyas an essential element, pressing and drying said web, then applying animal-glue sizing material to the surfaces only of the dry web, immediately applying volatilized formaldehyde to said surface-sized web,and finally drying the web immediately to prevent penetration of said animal-glue sizingmaterial and said formaldehyde into said body whereby said formaldehyde reacts with said animal-glue sizing material to harden the sur-' faces only of said web.

LEON M. YOERG. 

